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1.
Structure and health effects of inulin-type fructans have been extensively studied, while less is known about the properties of the graminan-type fructans in wheat. Arabinoxylan (AX) is another important indigestible component in cereal grains, which may have beneficial health effects. In this study, the fructan content in milling fractions of two wheat cultivars was determined and related to ash, dietary fibre and AX contents. The molecular weight distribution of the fructans was analysed with HPAEC-PAD and MALDI-TOF MS using 1H NMR and enzymatic hydrolysis for identification of fructans. The fructan content (g/100 g) ranged from 1.5 ± 0.2 in flour to 3.6 ± 0.5 in shorts and 3.7 ± 0.3 in bran. A correlation was found between fructan content and dietary fibre content (r = 0.93, P < 0.001), but with a smaller variation in fructan content between inner and outer parts of the grain. About 50% of the dietary fibre consisted of AX in all fractions. The fructans were found to have a DP of up to 19 with a similar molecular weight distribution in the different fractions.  相似文献   

2.
The lipid profile of nuts from Ximenia caffra and Ricinodendron rautanenii was determined and compared. Although the total oil content of X. caffra and R. rautanenii nuts was similar (47.6 ± 7.5% versus 53.3 ± 13.7%), the fatty acid profiles differed significantly. X. caffra had a higher content (p < 0.05) of saturated fatty acids than R. rautanenii (20.19 ± 1.07% versus 13.87 ± 3.68%) and contained C22:0 and C24:0 which were lacking in R. rautanenii. Total monounsaturated fatty acids were higher in X. caffra than R. rautanenii (71.48 ± 0.99% versus 36.66 ± 1.95%). Oleic acid (C18:1n9) was the major monounsaturated fatty acid (MUFA) in X. caffra whereas erucic acid (C22:1n9), the major MUFA in R. rautanenii, was undetectable in X. caffra. R. rautanenii had a greater polyunsaturated fatty acid content than X. caffra which contained C18:3n3 (α-linolenic acid) and nervonic acid (24:1n9). X. caffra is potentially an important source of essential fatty acids.  相似文献   

3.
The color (L*, a*, b* parameters), the total phenols content and the global chemical composition (moisture, protein, fat, carbohydrates and ash) of four fresh varieties of olive leaves (Chemlali, Chemchali, Zarrazi and Chetoui) were determined. Fresh olive leaves are characterized by a green color (greenness parameter, a*, varying from ?5.01 ± 0.26 to ?9.14 ± 1.21), an intermediate moisture content (0.85 to 1.00 g/g dry matter, i.e. 46 to 50 g/100 g fresh matter) and a variable amount of total phenols according to the olive leaf variety (from ≈2.32 to ≈1.40 g caffeic acid/100 g dry matter).Fresh leaves were submitted to blanching and/or infrared drying at 40, 50, 60 and 70 °C in order to be stabilized by reducing their moisture contents. The impact of IR drying temperature on some quality attributes (color, total phenols and moisture rate removal) was evaluated. Nevertheless, the effect of prior blanching treatment on the quality attributes of dried leaves is less significant and it depends on the olive leaf variety. The infrared drying induces a considerable moisture removal from the fresh leaves (more than 85%) and short drying durations (varying from ≈162 at 40 °C to 15 min at 70 °C). IR drying temperature showed a significant effect of on total phenols content and the color of the leaves whatever the leaf variety. In fact, total phenols content of dried olive leaves increased if compared to fresh ones. For example, total phenols of Chemlali leaves increased from 1.38 ± 0.02 (fresh leaves) to 2.13 ± 0.29 (dried at 40 °C) and to 5.14 ± 0.60 g caffeic acid/100 g dry matter (dried at 70 °C). IR drying allows preserving the greenness color of fresh leaves and enhancing their luminosity. It could be suggested for preserving olives leaves before their use in food or cosmetic applications.  相似文献   

4.
Aligned epoxy-matrix composites were made from hemp fibres defibrated with the fungi Phlebia radiata Cel 26 and Ceriporiopsis subvermispora previously used for biopulping of wood. The fibres produced by cultivation of P. radiata Cel 26 were more cellulose rich (78%, w/w) than water-retted hemp due to more degradation of pectin and lignin. The defibrated hemp fibres had higher fibre stiffness (88–94 GPa) than the hemp yarn (60 GPa), which the fibre twisting in hemp yarn might explain. Even though mild processing was applied, the obtained fibre strength (643 MPa) was similar to the strength of traditionally produced hemp yarn (677 MPa). The fibre strength and stiffness properties are derived from composite data using the rule of mixtures model. The fibre tensile strength increased linearly with cellulose content to 850 MPa for pure cellulose. The fibre stiffness increased also versus the cellulose content and cellulose crystallinity and reached a value of 125 GPa for pure crystalline cellulose.  相似文献   

5.
Thymus zygis ssp. gracilis shrubs were cultivated as an experimental crop under different watering level, in order to achieve 81, 63, 44 and 30% of the local potential evapotranspiration (ETo). After 4 years of cultivation, thyme leaves were analyzed on the basis of their essential oil (yield and quality), total phenolic content, free radical-scavenging activity and polyphenolic profile.Essential oil yield values ranged between (2.3 ± 0.7) and (3.6 ± 0.7)% for 81 and 30% ETo equivalent, respectively. The comparison of essential oil production at the 2nd and 4th years of cultivation showed that using watering levels higher than 30% ETo equivalents reduced significantly (P < 0.05) the essential oil yielded by these shrubs with time.Analysis of total phenolic content, polyphenolic profile, and radical scavenging activity were performed using post-distillation dry leaves. Total phenolic content values ranged from (122.2 ± 19.3) to (108.5 ± 19.2) mg of gallic acid equivalents (GAEs)/g of dry plant for the highest and lowest watering level treatment, respectively. Regarding the polyphenolic profile, rosmarinic acid, followed by apigenin, ferulic, carnosic and caffeic acids, was the phenolic component quantified at the highest concentrations. Radical-scavenging activities (IC50) concentrations varied from (3.7 ± 1.6) mg/mL for 81% ETo to (7.4 ± 2.3) mg/mL 30% ETo.In spite of the intra-specific variability detected, the individual analysis of shrubs has allowed the selection of plants which are characterised by having adequate levels of essential oil and polyphenolic extract (yield and quality), almost all of them being cultivated under a 60% ETo watering level. These selected shrubs will allow us to make further vegetative propagations in order to obtain homogeneous field crops with plants of contrasted quality cultivated under a 60% ETo watering level.  相似文献   

6.
Controlled environments were used to define the manner in which temperature, water and fertilizer affect the timing of key transition points during grain development and to investigate the effects of combined environmental factors in a US spring wheat (Triticum aestivum (L.)). When plants were subjected to very high temperature regimens (37/17  or 37/28 °C day/night) during grain development, the times to maximum kernel water content, maximum dry weight and harvest maturity were shorter than in plants maintained under a 24/17 °C day/night regimen. Starch accumulated at similar rates, but the onset and cessation of starch accumulation occurred earlier. Apoptosis in endosperm tissue also occurred earlier under high temperatures and coincided with physiological maturity. The addition of drought to the 37/17 °C regimen further shortened the time to maximum water content and dry weight and reduced the duration of starch accumulation, but did not influence the timing of protein accumulation or kernel desiccation. Post-anthesis fertilizer had little effect on time to maximum water content, dry weight, apoptosis, or harvest maturity under any of the temperature regimens and did not influence the timing of starch accumulation. However, both the rate and duration of protein accumulation were reduced when post-anthesis fertilizer was omitted.  相似文献   

7.
Fructans are prebiotics, with potentially beneficial effects on human health. This study aimed to examine genetic variation in wheat grain fructan content using a simplified analytical method. The method involves extracting fructans from wheat grain followed by enzymatic hydrolysis to break down fructans into monosaccharides that can then be quantitatively measured by anion-exchange liquid chromatography coupled with pulsed amperometric detection. The modified procedure is reliable and allows the handling of large numbers of flour samples at a low cost, and could therefore be useful for assessing large numbers of wheat breeding lines. Using this method, grain samples taken from 19 bread wheat cultivars and breeding lines grown in both glasshouse and the field were analysed for grain fructan content. In addition, grain samples of 29 international wheat landraces and 14 new wheat breeding lines from the International Maize and Wheat Improvement Center (CIMMYT) were surveyed for their fructan contents. There was significant genotypic variation among these materials, with grain fructan content ranging from 0.7 to 2.9% of grain dry weight. There was no evidence of strong genotype-by-environment interaction; the fructan contents of field-grown grain samples were positively correlated (r = 0.83) with those of glasshouse-grown samples of the same cultivars. It should therefore be possible to investigate the genetic control of variation for this trait using the simplified HPLC method and to select effectively for increased grain fructan content in wheat breeding.  相似文献   

8.
This study identified the role of milling and parboiling on arsenic (As) content and its species in large numbers of rice samples. Total As contents were 108 ± 33 μg/kg in polished rice grains (PR), 159 ± 46 μg/kg in unpolished rice grains (UR), 145 ± 42 μg/kg in parboiled polished rice grains (PPR) and 145 ± 44 μg/kg in parboiled unpolished rice grains (PUR). The percentages of inorganic As (iAs) were 66% ± 8% in PR and from 72% to 77% in other grain categories. The polishing process reduced the As content in the rice grains, removing outer part of the UR with high amount of As, whereas the parboiling technique transferred the semimetal content within the grain. Total As and iAs contents were not significantly different in UR, PPR and PUR, homogenizing its distribution inside the grains. The results allowed to understand how different operations affect As fate and its chemical forms in grains.  相似文献   

9.
This study is the small part of the big project related to the metallic contamination in foodstuff. The work presented here allowed determination the level of iron, copper, zinc, lead and cadmium in bread samples obtained from 20 bakeries in Ankara and Samsun, Turkey. The atomic absorption spectrophotometry method was used to determine these metals. The mean values of iron, copper, zinc, lead, and cadmium levels were found as 19·2±8·1 mg/kg-dry weight (dw), 2·1±1·0 μg/kg-dw, 10·0±3·0 μg/kg-dw, 86·8±176·0 μg/kg-dw, and 12·2±6·1 μg/kg-dw, respectively. No significant differences were found in copper and lead levels of samples obtained from bakeries in general, and in copper and cadmium levels of the samples from different provinces (P>0·05), while they were considered significant in iron, zinc, and cadmium levels of samples in general, and in iron, zinc and lead levels of samples from different provinces (P<0·05).  相似文献   

10.
《Field Crops Research》2004,85(2-3):213-236
Three different experiments were designed to study the effects of N fertilizer rate, timing and splitting, and the response to combined application of N and S fertilizer on the bread-making quality of hard red spring wheat (Triticum aestivum L.) over a 3-year period in Vertisols under rainfed Mediterranean conditions. The following parameters were analyzed: grain yield, test weight, grain protein content, gluten index and alveograph parameters (W: alveogram index; P: dough tenacity; L: dough extensibility; P/L: tenacity–extensibility ratio). The N rate experiment included rates of 0, 100, 150 and 200 kg N ha−1 applied on four different sites. The experiment was designed as a randomized complete block with four blocks. For the experiment on N timing and splitting, a single rate of 150 kg N ha−1 was used, different fractions being applied at sowing, tillering and stem elongation, at a single site; again, experimental design was a randomized complete block with four blocks. Finally, for the experiment on the response to combined application of N and S fertilizer, a single fertilizer dose of 150 kg N ha−1 was applied in two forms (urea+ammonium nitrate and urea+ammonium nitrosulfate) with one leaf application at ear emergence (zero, 25 kg S ha−1, 25 kg N ha−1, 25kgSha−1+25 kg N ha−1 and 50 kg N ha−1), also at a single site, using a split-plot design with four replications. Year-on-year variation in rainfall led to marked variations in wheat yield, grain protein content and bread-making quality indices. A close correlation was observed between rainfall over the September–May period and both grain yield and grain protein content (optimum values for both being recorded in the rainfall range 500–550 mm) as well as the alveogram index. A negative correlation was observed between mean maximum temperatures in May and both test weight and alveogram index (W). N fertilizer rate had a more consistent effect on bread-making quality than on grain yield. The highest values for grain yield were recorded at an N rate of 100 kg ha−1, while maximum grain protein content values were recorded at 150 kg ha−1. Application of half or one-third of total fertilizer N at stem elongation improved grain yield and grain protein content with respect to applications at sowing alone or at both sowing and tillering. Increased N rates led to a considerable increase in W values and to a reduction in the P/L ratio, thus improving dough balance, with a negative effect on the gluten index. Leaf application of N at ear emergence only affected grain protein content and the W index. Soil or leaf application of S had no effect on protein quality indices. The response of grain yield and grain protein content to fertilizer N differed from that reported for temperate climates.  相似文献   

11.
《Field Crops Research》2006,96(1):63-70
Pigeon pea (Cajanus cajan (L.) Millsp.) seedlings compete poorly against the rapid growth of warm-season annual weeds. Weed control is required before this heat and drought-tolerant legume can be reliably grown in the U.S. southern Great Plains as a potential source of livestock hay between annual plantings of winter wheat (Triticum aestivum L.). Currently, no herbicides are labeled for use on pigeon pea grown in the U.S. Three years of replicated field experiments were conducted to determine the effects of applications (1× and 2× rates) of herbicides (pre-emergence, sulfentrazone + chlorimuron and metribuzin; post-emergence, imazapic and sethoxydim) on weed suppression, pigeon pea dry matter, and carry-over effects on a winter wheat crop. The most abundant summer weeds were broadleaf, and all herbicide treatments, except sethoxydim (grass herbicide), reduced weed densities compared to untreated plots without adversely affecting pigeon pea stands. Imazapic treatments provided the most effective weed control. Overall average pigeon pea dry matter ranged from 75 to 256 g m−2 with sethoxydim and the untreated control ≤ metribuzin ≤ sulfentrazone + chlorimuron ≤ hand weeded control ≤ imazapic. Compared to the hand-weeded control, imazapic treatments greatly reduced wheat dry matter (1×, 65% and 2×, 91%) and grain yield (1×, 59% and 2×, 93%). Imazapic should not be used unless nontransgenic imidazolinone herbicide tolerant wheat cultivars are planted. While the other herbicides decreased negative effects of weeds on pigeon pea dry matter without greatly affecting productivity of a following wheat crop, appropriate labels for each of these herbicides will be required prior to their use by southern Great Plains pigeon pea producers.  相似文献   

12.
Evening primrose (Oenothera biennis) is increasingly cultivated for medicinal use of the γ-linolenic acid rich oil. The seed cake (EPSC) – the remaining industrial residue from cold pressing – was extracted with polar solvents in order to investigate a profitable polyphenolic recovery. The extractable matter and the total phenolic content (Folin-Ciocalteu) have been compared to a black currant residue from juice production (Ribes nigrum) and seed cakes from sesame, woad (Isatis tinctoria) and burdock (Arctium lappa). The EPSC crude extracts yielded the high total phenolic content (min 228.2 ± 11.6 to max 696.4 ± 29.0 mg GAE g−1 dry extract) within the range of already commercialized antioxidant extracts from rosemary (RO, 142.1 ± 1.9 mg g−1), green tea (GT, 446.8 ± 27.4 mg g−1) and grape seed (GS 790.0 ± 53.1 mg g−1). All extracts exhibited free radical scavenging activity (DPPH assay) with the order of potency: EPSC > GS > GT ≫ burdock = black currant > RO > butylated hydroxytoluene (BHT) ≫ woad > sesame. Accordingly EPSC extracts where very effective in scavenging superoxide anion radicals (neotetrazolium assay: GS > EPSC > GT ≫ BHT > burdock > woad > sesame) and inhibition of lipid oxidation (Rancimat assay: BHT ≫ GT > EPSC ≫ burdock > woad > RO > sesame > GS). Decreasing Rancimat activity from 80 °C upwards might indicate heat sensitiveness and limited usability. However, an efficient exploitation of polyphenols from evening primrose seed cakes in terms of an uncomplicated extraction procedure, the yield and the competitive profile as a strong radical scavenger can be concluded.  相似文献   

13.
《Field Crops Research》2006,96(1):125-132
The late-season foliar application of urea may increase yield and grain quality of wheat (Triticum aestivum L.). Limited information is available regarding the effect of late urea spraying on the performance of wheat cultivars under various basal N fertilization rates. Field experiments were conducted during 2000 through 2002 to evaluate the responses of six winter wheat cultivars to foliar urea (30 kg N ha−1) treatment around flowering at low (67 kg N ha−1) and high (194 kg N ha−1) basal N fertilization rates. Following urea spraying at low N rate, all cultivars increased grain yields to a similar extent (by an average of 7.8% or 509 kg ha−1) primarily due to an increase in the 1000-kernel weight. No yield response to the late-season urea treatment occurred at high basal N rate where grain yields averaged 24.9% (1680 kg ha−1) higher than those at low N rate. In contrast, late foliar urea application similarly improved grain quality at both low and high N rates by an average of 5 g kg−1 (4.5%) for protein content, 3.2 cm3 (11.9%) for Zeleny sedimentation, and 20 g kg−1 (8.6%) for wet gluten. These quality increments were consistent in all growing seasons regardless of significant variations in grain yields and protein concentrations across years. However, most cultivars failed to achieve breadmaking standards at low N rate as quality increments associated with the urea treatment were relatively small when compared to those achieved by high basal N rate. Late urea spraying had no effect on the falling number, whereas some cultivars showed small, but significant reduction in the gluten index at both N rates. Cultivars improved the hectolitre weight with the late-season urea treatment only at low N rate. Significant cultivar × urea interactions existed for most quality traits, which were due to the cultivar differences in the magnitude of responses. Thus, late-season urea spraying consistently produced larger yields at low basal N rate, and resulted in cultivar-dependent increases in protein content, Zeleny sedimentation, and wet gluten at both low and high N rates.  相似文献   

14.
《Field Crops Research》2005,91(2-3):319-327
The consumer's interest in natural, unconventional and nutritional foods led to the development of new specialty foods based on grain blends. Components of such foods are often so-called ‘ancient wheats’ which were never the subject of modern plant breeding programmes. Khorasan or Oriental wheat (Triticum turanicum) is a neglected and underutilised tetraploid wheat species, which probably survived over the centuries in subsistence farming systems in the Near East and Central Asia. In the present study the agronomic potential of Khorasan wheat was evaluated under eastern Austrian conditions.Fourteen accessions of Khorasan wheat were investigated together with check durum wheat cultivars over a period of 4 years in the Marchfeld region, north-east of Vienna. The crops were sown both in autumn and spring.The investigated material was inferior to modern durum wheats in most agronomic traits. No accession was found to tolerate soil temperatures below −5 °C. Tolerance to drought and fungal diseases was limited and/or modest, and grain yields were significantly lower. While the best performing turanicum accessions yielded in average 385.8 and 233.8 g m−2 for autumn and spring sowing, respectively, the check winter durum yielded 466.5 g m−2 and the check spring durums between 351.5 and 391.8 g m−2. Several characteristic and interesting features were observed which permit successful marketing of pure Khorasan grain or as a component in grain blends, despite possible flour quality traits. The grain has an impressive kernel size and thousand kernel weight, in most cases greater than 50 g and often even greater than 60 g. The high thousand kernel weight might be a valuable trait to transfer into durum wheat to improve grain yield. Moreover, the grain has an amber colour and high vitreousness.Due to higher plant height, low lodging tolerance and high susceptibility against powdery mildew, Khorasan wheat is more suitable for organic farming systems. Although there is evidence that Khorasan wheat has low adaptation, it is of interest as an alternative cereal to increase diversity both in the field and on the consumer's table. However, further experiments are necessary: on the one hand to study the interactions between sowing rates, sowing dates, weed suppression, thousand kernel weight and kernel plumpness in order to find out optimal production procedures, and on the other hand to find out areas/fields with the best growth conditions for Khorasan wheat.  相似文献   

15.
《Field Crops Research》2004,89(1):17-25
The pigeonpea (Cajanus cajan (L.) Millsp.) crop retains appreciable amounts of green foliage even after reaching physiological maturity, which if allowed to defoliate, could augment the residual benefit of pigeonpea to the following wheat (Triticum aestivum L.) in a pigeonpea–wheat rotation. The effect of addition of leaves present on mature pigeonpea crop to the soil was examined on the following wheat during the 1999/2000 growing season at Patancheru (17°4′N, 78°2′E) and during the 2001–2003 growing seasons at Modipuram (29°4′N, 77°8′E). At Patancheru, an extra-short-duration pigeonpea cultivar ICPL 88039 was defoliated manually and using foliar sprays of 10% urea (30 kg/ha) and compared with a millet (Pennisetum glaucum (L.) R.Br.) crop, naturally senesced leaf residue and no-leaf residue controls. At Modipuram, the effect of 10% urea spray treatment on mature ICPL 88039 was compared with the unsprayed control. At both locations, the rainy season crops were followed by a wheat cultivar UP 2338 at four nitrogen levels applied in a split plot design, which at Patancheru were 0, 30, 90 and 120 kg N ha−1 and at Modipuram 0, 60, 120 and 180 kg N ha−1. At Patancheru, urea spray added 0.5 t ha−1 of extra leaf litter to the soil within a week without significantly affecting pigeonpea yield. This treatment, however, increased mean wheat yield by 29% from 2.4 t ha−1 in the no-leaf residue pigeonpea or pearl millet plots to 3.1 t ha−1. At Modipuram, the foliar sprays of urea added more leaf litter to the soil than at Patancheru. Here, increase in subsequent wheat yield due to additional pigeonpea leaf litter was 7–8% and net profit 21% more than in the unsprayed control. The addition of pigeonpea leaf litter to the soil resulted in a saving of 40–60 kg N for the following wheat crops in both the environments. The results demonstrated that pigeonpea leaf litter could play an important role in the fertilizer N economy in wheat. The urea spray at maturity of the standing pigeonpea crop significantly improved this contribution in increasing wheat yield, the effect of which was additional to the amount of urea used for inducing defoliation. The practice, if adopted by farmers, may enhance sustainability of wheat production system in an environmentally friendly way, as it could reduce the amount of fertilizer N application to soil and enhance wheat yield.  相似文献   

16.
《Field Crops Research》2006,98(1):52-59
This study explored whether the average grain weight of wheat tends to be reduced when grain number is increased due to either competition or, to a consistent increase in the relative proportion of grains of smaller weight potential. Three field experiments considering environmental, genetic and environmental × genetic effects on yield and its main components were analysed during the 2003/2004 growing season in two different locations within the Mediterranean area of Catalonia, Spain. The relationship between grain weight and number of grains per unit land area was analysed for both the average of all grains (AGW) and for grains in specific positions of the main-shoot spikes: proximal (CPg) and distal (CDg) grains of central spikelets, and proximal grains of the near apical (APg) and near basal (BPg) spikelets. The proportional contribution of grains per spike for the different grain positions and the relative contribution of spikes per m2 made by the main shoot or tillers were also examined.In the three experiments, AGW was reduced when grain number was increased due to genetic and/or environmental factors. However, the slopes of the straight-lines that represented the negative relationship between grain number and grain weight were lower (less negative) and less significant for CPg (b = −0.20, P > 0.20), CDg (b = 0.06, P > 0.20) and BPg (b = −0.21, P > 0.20) than for AGW (b = −0.40, P < 0.05). The proportional contribution of distal grains and tiller spikes (both with relatively light grains) were directly related to grain number increases. Therefore, as grain number increased there was a higher proportion of grains of low potential weight. Thus, the average grain weight was concomitantly reduced when grain number increased by increasing the proportion of “small grains” in the canopy independently of any competitive relationship between growing grains.  相似文献   

17.
Rotation of winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.) is the prevailing double-cropping system in the North China Plain. Typically, winter wheat is planted at the beginning of October and harvested during early June. Maize is planted immediately after wheat and harvested around 25th of September. The growing season of maize is limited to about 100–110 days. How to rectify the sowing date of winter wheat and the harvest time of summer maize are two factors to achieve higher grain yield of the two crops. Three-year field experiments were carried out to compare the grain yield, evapotranspiration (ET), water use efficiency (WUE) and economic return under six combinations of the harvest time of summer maize and sowing date of winter wheat from 2002 to 2005. Yield of winter wheat was similar for treatments of sowing before 10th of October. Afterwards, yield of winter wheat was significantly reduced (P < 0.05) by 0.5% each day delayed in sowing. The kernel weight of maize was significantly increased (P < 0.05) by about 0.6% each day delayed from harvest before 5th of October. After 10th of October, kernel weight of maize was not significantly increased with the delay in harvest because of the lower temperature. The kernel weight of maize with thermal time was in a quadratic relationship. Total seasonal ET of winter wheat was reduced by 2.5 mm/day delayed in sowing and ET of maize was averagely increased by 2.0 mm/day delayed in harvest. The net income, benefit–cost and net profit per millimetre of water used of harvest maize at the beginning of October and sowing winter wheat around 10th of October were greater compared with other treatments. Then the common practice of harvest maize and sowing winter wheat in the region could be delayed by 5 days correspondingly.  相似文献   

18.
Changes in fatty acids were studied during maturation of coriander (Coriandrum sativum L.) fruits cultivated in the North-East of Tunisia (Charfine). The fruits matured in 55 days after flowering (DAF). Oil and petroselinic acid synthesis proceeded at a steady rate up to 32 DAF. The first results showed a rapid oil accumulation started at newly formed fruits (9.6 ± 0.2%) and continued until their full maturity (26.4 ± 0.5%). During fruit maturation, fatty acid profiles varied significantly among the nine stages of maturity. At the 32th DAF, palmitoleic, gadoleic, erucic and docosahexenoic acids were not detected and petroselinic acid had a highest amount (84.8 ± 4.5%). Fruits development resulted mainly in an increase of petroselinic acid and a decrease of palmitic acid (C16:0). At full maturity, the main fatty acids were petroselinic acid (80.9 ± 5.7%), followed by linoleic (13.6 ± 2.9%), palmitic (3.6 ± 0.1%) and stearic (0.7 ± 0.1%) acids. Saturated and polyunsaturated fatty acids decreased significantly and monounsaturated fatty acids increased during maturation of coriander fruit. Coriander fruits at the first four stages of maturity have a healthy nutritional value and the last five stages were with important economic and industrial applications. Results of this study indicate that the variation in the fatty acid composition of coriander fruit during maturation may be useful in understanding the source of nutritionally and industrially important fatty acids in this fruit. Coriander fruit is potentially an important source of petroselinic acid which has numerous industrial applications.  相似文献   

19.
Arabinoxylans (AXs) are the major dietary fiber (DF) component in wheat and their consumption has been associated with several health benefits. Genetic improvement of the AX in refined wheat flour could be a good solution to improve the DF daily consumption while maintaining the flour desirable quality. In this study, 193 common wheat lines were analyzed for their AX content in refined flour and end-use quality. Wide variation in both the total arabinoxylan (TOT-AX) (10.8–16.5 mg/g) and water-extractable arabinoxylan (WE-AX) (3.2–7.6 mg/g) was identified and, in both cases, the genotype had the greatest impact on the observed phenotypes. Variation in the endogenous AX fractions appeared to have a moderate effect on wheat quality. The WE-AX, specifically, were positively correlated with gluten strength (r = 0.11 to 0.32) and bread loaf volume (r = 0.16), whereas the TOT-AX were negatively correlated with dough extensibility (r = −0.11) and bread making quality (r = −0.11). Overall, results of this study show that the genetic improvement of grain AX is feasible and that the AXs present in refined flour do not dramatically alter wheat quality indicating that it is possible to select varieties with high AX endosperm content end desired end-use quality.  相似文献   

20.
Cuphea (Cuphea viscosissima Jacq. × C. lanceolata f. silenoides W.T. Aiton, line PSR23) is a new crop being developed in the North Central United States, as an industrial oilseed crop. Cuphea PSR23 seed oil is rich in medium-chain-length fatty acids such as capric acid used to manufacture soaps and detergents. The objective of this research was to determine the time when physiological maturity of cuphea seed is reached and how seed development affects seed moisture, weight, oil content, fatty acid content, germination, and seedling vigor. To evaluate seed development, 2000 cuphea flowers were tagged at anthesis in the field at Prosper, North Dakota in 2004 and 2005. Each flower was tagged when open and the position on the main stem or branch was recorded. Two hundred capsules from the tagged flowers were harvested at 3- to 4-d intervals from 5- to 48-d post anthesis (DPA). Seed weight increased as a function of growing degree days (GDD) and the days from anthesis. Physiological maturity occurred when maximum dry seed weight was attained. Seed weight increases followed the Gompertz function with a R2 = 0.90 (2004) and R2 = 0.95 (2005). All capsules, regardless of their position on the stem, followed the same growth function for seed weight. The maximum dry seed weight estimated by the Gompertz function was 3.61 for 2004 and 3.58 mg seed−1 for 2005. Physiological maturity estimated with a quadratic function occurred at 38 DPA or 270 GDD in 2004. In 2005, physiological maturity occurred at 26 DPA or 265 GDD. As a visual indicator when the capsules split-open seeds inside that capsule are physiologically mature. Seed moisture decreased from 900 g kg−1 at 37 GDD post anthesis to 450 g kg−1 at 319 GDD post anthesis in 2004; however, in 2005 seed moisture decreased from 850 to 81 g kg−1 at 293 GDD post anthesis. Seed germination increased as seed developed and it was 83% when harvested 234 GDD post anthesis. Oil content increased from 98 g kg−1 at 37 GDD post anthesis to 279 g kg−1 319 GDD post anthesis. Fatty acid composition varied throughout seed development. Seed development for 111 GDD and greater had more than 66% of capric acid (10:0). Cuphea should be harvested after 265 GDD post anthesis when most capsules on the main stem are split-open, have attained maximum seed weight, germination, seedling vigor, and oil content.  相似文献   

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